Generally speaking, ionic liquids refer to a specific class of molten salts which are liquid at temperatures of 100° C. or below. Ionic liquids have very low vapor pressure and generate virtually no hazardous vapors. Due to the charged species comprising the ionic fluids, they provide a highly polar medium.
In recent years, there is much interest in this class of novel materials. Ionic liquids have been extensively evaluated as environmental-friendly or “green” alternatives to conventional organic solvents for a broad range of organic synthetic applications. In addition, ionic liquids have also been used in organic synthesis applications as catalysts. Conventional ionic liquids for a wide range of chemical processes are described in “Ionic Liquid” by J. D. Holbrey and K. R. Seddon, and in Clean Products and Processes, Vol. 1, pp. 223-236 (1999). Other examples of ionic liquids are described in U.S. patents: U.S. Pat. No. 6,048,388; U.S. Pat. No. 5,827,602; U.S. patent Publications: US 2003/915735A1; US 2004/0007693A1; US 2004/0035293A1; and PCT publications: WO 02/26701; WO 03/074494; WO 03/022812; WO 04/016570.
Furthermore, ionic liquids have also been found useful in chemical separation and extraction, as described, for example, in WO 02/074718.
Ionic liquids also have applications in electrochemistry, for example, in fuel cells, electrodeposition processes and other electrochemical applications.
Additionally, ionic liquids have been shown to be effective in applications where water-based chemistry can be problematic (for example, applications involving proton transfer or nucleophilicity), or in applications where certain coordination chemistry could have a damaging effect on the substrates involved.
Moreover, ionic liquids have found applications in consumer product formulations and industrial product formulations for surface treating, air treating, cleaning and other benefits, as described in US 2004/0077519A1.
It is desirable to develop new classes of ionic liquids by converting certain conventional solid or semi-solid actives used in consumer or industrial product formulations into ionic liquids. Thus, the ionic liquids can be used as replacements of the traditional actives, such as surfactants, and are easier to incorporate into the formulations. Moreover, new classes of ionic liquids can be derived from selective pairings between functional actives (for example, surfactant derived anions can be paired with softener derived cations) such that the resulting ionic liquids can have multiple active functionalities to provide multiple benefits that previously require multiple actives in the formulation to achieve.
It is also desirable to develop new classes of ionic liquids with advantageous properties. For example, the ionic nature and/or fluidity of these novel ionic liquids provide additional advantages, such as improved soil removal capability, lower viscosity of the formulation, higher concentration of the active functionalities can be incorporated.